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91.
扩大企业对CDM的参与是提高清洁发展机制减排效果的关键因素,但是随着参与的不断扩大,可能产生价格因素、小项目开发障碍、“普遍性”等阻碍因素,将影响企业对CDM参与性的继续扩大,对减排效果的提高造成负面影响。在对企业参与和CDM环境效力相互关系探讨的基础上,本文对如何继续扩大参与、加大减排提出了发展建议。  相似文献   
92.
Homeobox genes regulate development of digits, and it has been suggested that the ratio of length of second to length of fourth digit reflects such genetic effects in a sex-specific manner. We show that digit ratios in the sexually dichromatic house sparrow Passer domesticus differ between sexes, with males having higher ratios than females, and that individuals produce consistent ratios on the two feet. If Homeobox or other genes had pleiotropic effects on development of digits, behavior, and physiology of males and females, we would expect secondary sexual characters and immunity to be related to digit ratio in a sex-specific manner. The size of the visible part of the black badge in February (a secondary sexual character), but not total badge size, was positively correlated with digit ratios, suggesting that males with more male-like digit ratios had larger visible badges. Because of sex-specific effects of development on secondary sexual characters and immunity, we predicted sex-specific differences in immune response to be related to digit ratio. House sparrows with large digit ratios had weaker T cell-mediated immune response than individuals with small digit ratios, particularly in females, implying that females with more male-like digit ratios had weak immune responses. These findings are consistent with the hypothesis that early development, as reflected by digit ratios, and genetics affect the expression of adult characters that are supposedly strongly contributing to fitness.  相似文献   
93.
94.
This paper is concerned with the sustainable development of a self-drive tourist destination in the remote region in Northern Australia. It first compares officially used data on visitor profiles to the information collected in the survey. Differences between data collected and available secondary data imply that tourism planning should include collection of region-specific tourism information to guide and mitigate potential environmental changes. Natural landscape features are the key attraction for visitors to the region. Visitor satisfaction levels with the current state of the destination are high. However, local residents reported perceived negative impacts of tourism, in particular on amenities and the ecology of the landscape. Visitors also reported behavior that might contribute to environmental impacts. Implications of the findings, in the context of future destination planning, are discussed.  相似文献   
95.
在分析鄂西生态文化旅游产业集群发展的效应和意义的基础上,提出了鄂西生态文化旅游产业集群发展所遵循的市场导向、规划指导、产业互动、择优扶强、注重创新和可持续发展的原则,重点发展以旅游中心城市为依托的旅游服务业集群、以核心吸引物为中心的综合旅游产业集群、以旅游景观廊道为依托的餐饮购物业集群、以特色村镇为依托的旅游文化产业集群、以生产基地为依托的旅游商品产业集群,需要在产业要素整合、龙头企业培育、公共服务提供、重点项目建设、产品结构优化、区域品牌建设等方面推进鄂西生态文化旅游产业集群发展.  相似文献   
96.
Climate change adaptation now occupies central stage on the agenda of most environmental initiatives in Africa. Our current understanding on the state of adaptation is limited, however, both globally and in Africa in particular. This study examines the status of adaptation in the Sahel by reviewing the primary peer review literature that reports concrete climate change adaptation actions. Based on an analysis of 70 peer review papers that document 414 discrete adaptations, we create a snap shot of adaptations developed between 1975 and 2015, and also calculate the percentages of adaptation. The results show that from a country to country perspective, Kenya has the highest number of reported adaptation actions (75 or 18.1%). The percentages indicate that the adaptive capacity of the entire study area is generally low for all the countries being that the highest country-level percentage is recorded in Kenya and it is 18%. Regionally, West Africa has more adaptation actions (261 or 63%) when compared to other regions of the Sahel. Regional level percentages suggest a higher level of adaptation at the regional level being that the percentage falls within the high scale range. The most commonly used adaptation actions reported are income diversification and water harnessing respectively. When categorized, technically related adaptation actions dominate the adaptation charts. The decade 2008–2016 recorded the highest number of adaptations (65.2%). Adaptation actions are also reported to be triggered by climatic and non-climatic drivers which both record high frequencies but the climatic drivers (98%) of adaptation are slightly dominant relative to the non-climatic drivers (95%). These results should be viewed as proxies of climate change adaptation as much information may be found in grey literature and non-peer review national communications which are left out here because of their relative low standardization and acceptability due to the absence of peer review.  相似文献   
97.
Fish production and marketing are as old as the rural communities involved in the lucrative occupation in Badagry area of Lagos State, Nigeria. A random sampling of 200 fishermen using Participatory Rural Appraisal techniques (PRA) in five Badagry villages was used to explore coastal fishing and socio-economic development in the study area with a view to enhancing local productivity and sustainability. The findings show that an average fisherman in Badagry is aware of the resources available in his environment, and can affect productivity levels positively if given adequate incentives. There are two lessons from this study; one has to do with what PRA tells us about the fishing community, the other is the importance of facilitators that have, amongst other things, good listening skills. The experience also revealed that field workers’ ability to listen and learn from local fishermen was a critical factor in collecting in-depth information that could be used for rural community planning.  相似文献   
98.
The concept of carrying capacity is derived from ecology, with widespread contentions of its theoretical connotations and applications in the international academic community, especially the impact of human activities on the environment. Disputes on carrying capacity have been occurring not only among biologists and ecologists, but also among mainstream economists. Based on their efforts, the author makes an attempt to describe its origin, connotations, problems, measurement, and at the same time note the latest international progress in this field.  相似文献   
99.
基础设施与区域经济发展环境   总被引:23,自引:0,他引:23  
基础设施及其所形成的环境是人类自己营造的基础物质环境之一。是区域经济发展环境的主要组成部分。本文从四方面系统阐述了基础设施与区域经济发展之间的关系。提出了基础设施的引导与从属功能、带状经济的激发器和助推嚣等观点。分析了基础设施在改瞢生产环境与效率、空间经济集聚与扩散中的作用。以及基础设施短缺对区域经济发展的影响等。同时时归纳总结了我国土范国内已经形成的基础设施走廊的基本概况。  相似文献   
100.
A review of the use of planning and design briefs by local authorities in the United Kingdom was carried out in 1982–83 to test whether the role of the brief as an instrument of local policy and as a promotional tool in the development process was being fully exploited. The paper provides a state of the art review, presents a summary of the findings and offers some comments on the results. It concludes that most authorities now use briefs as part of their normal planning procedures, but that there is potential which is not yet being exploited.  相似文献   
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